Along with rapid popularization of broadband networks, it has become an important subject for optical transceiver modules to increase the operation speed, reduce the size and lower the consumption power. In Metro-area optical communication networks that connect between cities and relay stations, it has been demanded to transmit high speed signals at a communication rate of 10 Gbps through long-distance fibers of from 40 km to 80 km without relay. Further, a trend of increasing the communication speed to 40 Gbps or higher in relay stations, data centers and for short-to-medium distance fiber transmission of about 10 km has become active.
The present invention intends to provide a semiconductor optical modulation device and a semiconductor optical integrated device suitable to high speed, reduced-size and less power consuming optical transceiver modules at a reduced cost.